The contact owns a 2013 Toyota Prius. The contact stated while driving at approximately 25 MPH and depressing the brake pedal to slow for a traffic sign, the vehicle was not slowing down. The contact pumped the brake pedal several times before the vehicle slowed down. The contact stated that an unknown warning light was illuminated. The contact had the vehicle towed to a local dealer, where it was diagnosed and determined that the brake booster and brake actuator had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was unknown.